This invention is directed toward an improved peat harvesting method. The invention is also directed toward an improved, mobile, peat harvesting machine for carrying out the method.
Mobile, peat harvesting machines are well known and comprise a wheeled chassis having a peat collecting tank thereon. A peat collecting head is mounted on the unit and is operatively connected to the tank with a duct. Means on the chassis mount the collecting head with its inlet close to the ground. Fan means are provided for creating a reduced or negative pressure at the inlet of the collecting head so that peat can be drawn up off the ground into the collecting head and passed through the duct into the collecting tank. Means are also provided for manually adjusting the height of the inlet in the collecting head above the ground. This height is adjusted to obtain the most efficient collection of peat and is dependent, among other things, on the dryness and the density of the peat, and the power of the fan.
In use, the known peat harvesting machine is pulled along over the peat to be harvested by a tractor with the inlet of the collecting head set at the optimum height above the peat, and with the fan operating. As the machine moves along, peat is drawn up from the ground by the collecting head and deposited in the tank. The tractor operator drives the machine in a genrerally straight line and at the same time tried to keep a watch on the harvesting machine behind to ensure that the inlet on the collecting head is always at the optimum height relative to the peat being collected. Often the collecting head, set to one side of the wheeled chassis carrying the tank, will pass over hollows or mounds that do not affect the chassis carrying the head. The tractor operator however looks for the hollows or mounds and tries to manually adjust the height of the collecting head with suitable actuating means from his seat on the tractor so that the inlet of the head generally follows the contour of the land at the optimum height.
It can be difficult for the tractor operator to keep both the tractor on line, and the inlet on the collecting head at the optimum height. Usually the height of the inlet in the collecting head varies considerably due to slow responses from the operator to a change in contour. When the inlet height varies, so does the peat collection efficiency. If the inlet height increases, from the optimum height, less peat is picked up blocking the inlet. In addition, the inlet in the collecting head could be damaged if the head touches the ground. Because of the difficulty in keeping both the tractor on line, and the inlet on the collecting head generally at the optimum height, the amount of peat collected during each run is quite variable.